Here's Why Meghan Markle Can't Wear a Tiara, But Kate Middleton Can

With the royal wedding of Prince Harry and Meghan Markle now just months away, it stands to reason we might catch a glimpse of the American actress sporting a tiara during a formal event or two in the coming weeks. After all, she's basically in with the royal family now, and Kate Middleton has been seen wearing one on no fewer than six separate occasions. But as it turns out, our hopes of seeing photos surface of Markle at Kensington Palace in a crown will have to wait—and there's a very specific reason why.

According to The Mirror, it's strict British etiquette that dictates why Kate Middleton can wear a tiara, and Markle can't. And it boils down to one thing: marriage.

Tradition in the United Kingdom prohibits unmarried women from wearing tiaras—and in fact, the accessory is much more than just a gorgeous proclamation of royal affiliation. As explained by etiquette expert Grant Harold in an interview with BBC, the tiara has even more historical significance than simply proving royal affiliation: Through its doubling as a signifier of betrothal, it shows—in British culture—that one is off the market and not looking for a husband.

That's why, following her marriage to Prince William, Kate (now the Duchess of Cambridge) became immediately eligible to wear one. And after her royal nuptials in May of this year, Markle will be allowed to do the same.

So when exactly will we see the American actress in the bejeweled headpiece? Well, if history repeats itself, we could very well see Markle wearing one on her wedding day—Kate Middleton did for her wedding to Prince William, after all. But generally speaking, per royal etiquette, tiaras are an evening-only accessory, so it's also a possibility that the bride-to-be will until after her spring wedding to make her first appearance in a royal tiara.

Then again, the actress has been known to break a royal rule or two. So—as always with all things Meghan and Harry—let the guessing games begin!